On our walk west of Erjos, the first 'Yellow Composite' seen beside the track was a massive rosette of leaves supporting a single flowering stem that splits to support some large yellow flowers.
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| Erjos, Teno Region, Tenerife. |
Calling it Sonchus acculis is based on a brief description in the 'Natural History of Tenerife' but without a full description being available there is room for considerable error, especially as Tenerife has apparently 700 endemic plant species.
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| 'Dandelion' type Flower |
Apart from the large size the other strange feature of the flower buds is that they are covered in a thick layer of white hairs. This is especially thick on the un-opened buds where you almost think they are covered in some form of fungal growth.
Some flowers have less of these white fluffy hairs so you can see the bracts, or they may just be wearing off.
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| Single plant showing leaf rosette. |
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| Leaf with spiky margin. |
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| Large size apparent in this photo. |
We continued our walk past the transmission towers and into the laurel forrest where we found more of these plants. Sometime the rosette is not on the ground but supported on a brown stalk which old leaves hanging down.
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| Rosette supported on woody stalk. |
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| Detail showing achene. A paper on the evolution of Tree Sonchus can be found on the Internet. Proc. Natl. Acad. Sci. USA Vol.93,pp.7743-7748,July1996 Evolution A common origin for woody Sonchus and five related genera in the Macaronesian islands: Molecular evidence forextensiveradiation |
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